A submm-wave/far IR uncooled bolometer system and applications

The detection of radiation in the range of submillimeter and far infrared wavelengths has various applications in remote passive radiometric sensing, some times called as thermosensing, such as imaging of field targets, power line surveys, night vision, radio meteorology, atmospheric propagation and astrophysics. Developments directed to potential interest for telecommunications in that band have been increasing in recent years. The development of a non-imaging bolometer detector for incoherent radiation in the submillimeter bands is presented. Construction details are presented for a detector´s active material using polycrystalline and amorphous silicon. We describe the bandpass filters to be placed in front of the detector, which are being designed to be constructed using the resonant mesh technology, centered at the peak frequencies around 220, 410 and 670 GHz. The bolometric system will be submitted to qualification and performance tests at the focal plane of a 1.5-m submillimeter reflector located at a high altitude dry site (El Leoncito, Argentina Andes), using the Sun as a source of blackbody radiation, and a beacon transmitter at 410 GHz located in the far field with respect to the reflector. The first applications considered for the system are measurements of atmospheric propagation, solar imaging and tentative detection of solar transients (flares) in the selected bands.